Mounting adapter for the ram of power presses



H. E. IHLE 3,386,324

MOUNTING ADAPTER FOR THE RAM OF POWER PRESSES Jun 4 68 2 Sheer. t 1

Filed Aug. 25, 1966 INVENTOR. HANS E,1 E

ent

June 4, 1968 H. E. IHLE 3,

MOUNTING ADAPTER FOR THE RAM OF POWER PRESSES Filed Aug. 25, 1966 2 Sheets-Sheet 2 INVENTOR. HANS E. IHLE Agent United States Patent 3,386,324 MOUNTING ADAPTER FOR THE RAM OF POWER PRESSES Hans E. Ihle, Smyrna, Ga., assignor to Lockheed Aircraft Corporation, Burbank, Calif. Filed Aug. 23, 1966, Ser. No. 574,455 4 Claims. (Cl. 83-543) This invention relates to power presses, especially the massive stamping and punching type in which a heavy movable ram acts against a stationary bed, and more particularly to an adapter by which the head of the ram of such a press is mounted for predetermined lateral as well as universal movement relative to the bed.

In power presses it is important that the impact force applied thereby to the workpiece be equally distributed, i.e., be applied perpendicular to the workpiece surface over the entire area thereof. It is also important that the relative position of the die elements be precisely located and maintained throughout the forming or cutting operation of the press. Special die sets employing close tolerance positioning and guide elements are employed between the movable ram and the bed of the pres-s to facilitate this. However, such die sets are totally ineffective against irregular ram/ bed movement-s during operation of the press.

Considerable efforts have been directed in the design and manufacture of these presses, particularly the movable ram element thereof, to assure a true vertical stroke and a lengthy life in service. In spite of such elforts, however,

wear occurs due in large measure to the magnitude of the pressures and forces necessarily involved and the difficulty in maintaining such pressures and forces balanced. Lateral play inevitably develops accelerating the wear between the ram element and the associated supporting and guide members and compounding the problem by damage to the die sets.

Attempts to improve these conditions have been made through the use of universal joints capable of limited swiveling operatively connected in or to the ram element to assure proper alignment. This necessarily results in limited transverse movement of the ram relative to the bed and to such extent serves to prolong the life of the press .by reducing the wear of the ram guides or gibs. The specific design of these joints, however, is such that relative lateral movement is unduly limited plus the application of these joints is restricted to relatively small rams,

The present invention is directed to improvements in this area of the art and essentially proposes an adapter for the ram element of a press which may be designed into generally conventional presses with minimum interface change or constructed as an integral unitary assembly capable of attachment to existing presses. In either case, this adapter is connected to the press between the ram and the adjacent element of the die set so as to become for all intent and purposes an integral part thereof.

More specifically, this adapter is formed by a pair of generally parallel plates separated by a resilient member adjacent their outer marginal edges which are in radially spaced relation and where they are clampingly engaged. Internally the plates are formed or otherwise provided with coacting surfaces at the center thereof and also adjacent their marginal edges. These coacting surfaces are concentric about the center of the plates, and the adjacent surfaces of the plates between the concentric surfaces are maintained in spaced relation at all times whereby the plates are free to nutate or wobble, At the same time, the configuration of the coacting surfaces is such that the plates are free for relative lateral translation while their adjacent surfaces remain in contact.

With the above and other objects in view as will be apparent, this invention consists in the construction, combination, and arrangement of parts all as hereinafter more fully described, claimed, and illustrated in the accompanying drawings wherein:

FIGURE 1 is a perspective view partly in section of an adapter constructed in accordance with the teachings hereof located as it would be with respect to a typical die set when secured to the lower face of the ram of a power press; and

FIGURE 2 is a transverse section taken along the line 2--2 of FIGURE 1 and showing a fragment of the press ram to illustrate the freedom of movement of the adapter parts within predetermined limits to tilt, rotate and slip laterally in any direction.

Referring more particularly to the drawings, 10 designates .a base or bed of a power press and 11 a ram for coaction therewith in the forming or stamping of parts from stock material or workpieces. Typically, a die set 12 is employed in the press between the bed 10 and ram 11 to retain, align and guide the punch and/or die elements during the press operation. Such a die set 12 comprises a pair of parallel generally horizontally disposed plates, the upper plate 13 constituting a punch holder, for example, and the lower plate 14 constituting a die shoe. The adjacent surfaces of the plates 13 and 14 are provided with appropriate means to locate and hold the punch and die elements. The corners of each plate are pierced by openings which align one with the other and each associated pair of such openings includes a bushing 15 in which a guide pin 16- is mounted. When operatively installed in a press, the lower plate 14 is normally anchored to the bed 10 while the upper plate 13 is similarly connected to the ram 11.

According to the present invention, an adapter 17 is interposed between the upper plate 13 and the ram 11. This adapter 17 comprises an upper unit 18 adapted to be immovably attached to the ram 11, for example, through a number of clamps 11' and a lower unit 19 adapted to be similarly attached to the upper plate 13, for example, by a number of fasteners 13. The upper and lower units 18 and 19 are assembled as a unit by means of and through an annular member or connecting ring 21 which is carried by the upper unit 18 and projects therefrom in the direction of the lower unit 19 terminating in a lateral flange 22 which overlaps a similar flange 23 on the lower unit 19. These coacting flanges 22 and 23 are de signed to be disposed in spaced relation one to the other and are separated by resilient spacing means such as a polyurethane ring 24.

Thus disposed, the upper and lower units 18 and 19 are separated by an intermediate plate 25 between their adjacent surfaces. The adjacent surfaces of the upper unit 18 and the intermediate plate 25 are formed with complementary projecting and recessed surfaces that are concentric about the upper unit 18. To this end, the upper unit 18 is formed or otherwise provided with a semicircular enlargement 26 defined by a generally spherical surface at its center and the adjacent surface of the plate 25 has a depression 27 having a corresponding shape. A separate annular projection 28 is formed or otherwise provided on the upper unit 18 and a corresponding cavity 29 in the plate 25. The outermost surfaces, with respect to the center or semicircular enlargement 26, of the projection 28 and cavity 29 are angular, preferably at about 40 off the horizontal plane, and the surfaces of the plate 25 and upper unit 18 except for those associated with the enlargement 26 and projection 28 are designed to be disposed in constant space relation. This is accomplished by the amount of projection of the enlargement 26 compared with the depth of the coacting depression 27 whereby a single center area of contact in effect is established between the upper unit 18 and the plate 25. The projection 28 and its cavity 29 is appreciably greater than the depression 27 so that the upper unit 18 is capable of nutating or wobbling freely with respect to the plate 25 and lower unit 19.

At the same time, the dimensions of the lower unit 19 are substantially less than the effective dimensions of the upper unit 18 as established by the annular member 21. A circumferential space 30 is thereby produced when the members are assembled as described. This permits a predetermined relative lateral displacement between the upper and lower units 18 and 19 and antifriction means in the form of cutouts 31 in the adjacent surfaces of these units is incorporated therein to facilitate such displacement. Similar cutouts 32 may be provided in the upper face of the plate 25 adjacent the enlargement 26 if desired.

In view of the foregoing construction and arrangement, the misalignments of the ram 11 out of the true vertical position due to worn gibs or otherwise is corrected by the present adapter 17. Thus, regardless of the angle off the vertical of the ram 11 with respect to the die set 12, the force exerted thereby in the operation of the press will be applied in a uniform and horizontal plane on the die set and hence on the workpiece through the punch and die elements.

It is to be understood that the disclosure hereinabove is directed to a preferred embodiment of the invention. Numerous variations to this embodiment will suggest themselves to those skilled in the art. The appended claims are intended to cover all such variations and alterations as fall within the true spirit and scope of the invention and alone define the limitations to be placed thereon.

What is claimed is:

1. A mounting adapter for the ram of a power press incorporating a die set to locate and retain die elements in a predetermined relative position in the press between the ram and bed components thereof during its operation comprising:

a pair of plates adapted to be mounted between said ram and said die set;

an intermediate plate disposed between said pair of plates;

coacting concentric surfaces on one of said pair of plates and said intermediate plate at the center and adjacent the marginal edges thereof, said surfaces establishing the sole areas of contact between said one and said intermediate plates and said center surfaces being generally spherical;

a space between said one and said intermediate plates radially inward of and from the marginal edge surfaces aforesaid whereby said one plate is capable of nutation about said center surfaces;

a resilient member between the marginal edges of said pair of plates radially outward of said concentric surfaces; and

a clamp engaging said pair of plates across said resilient member, said clamp applying a uniform force less than that required to fully compress the resilient member.

2. The adapter of claim 1 wherein said surfaces adjacent the marginal edges are disposed at an angle of approximately 40 off the horizontal sloping toward said center surfaces.

3. The adapter of claim 1 including antifriction means between selected areas of the adjacent surfaces of said plates.

4. The adapter of claim 3 wherein said antifriction means includes cutouts in adjacent surfaces of the other plate and said intermediate plate.

References Cited UNITED STATES PATENTS 2,445,574 7/1948 Grunow 83-637 2,636,433 4/1953 Wennberg. 3,111,053 11/1963 Svensson 83543 X ANDREW R. JUHASZ, Primary Examiner. 

1. A MOUNTING ADAPTER FOR THE RAM OF A POWER PRESS INCORPORATING A DIE SET TO LOCATE AND RETAIN DIE ELEMENTS IN A PREDETERMINED RELATIVE POSITION IN THE PRESS BETWEEN THE RAM AND BED COMPONENTS THEREOF DURING ITS OPERATION COMPRISING: A PAIR OF PLATES ADAPTED TO BE MOUNTED BETWEEN SAID RAM AND SAID DIE SET; AN INTERMEDIATE PLATE DISPOSED BETWEEN SAID PAIR OF PLATES; COACTING CONCENTRIC SURFACES ON ONE OF SAID PAIR OF PLATES AND SAID INTERMEDIATE PLATE AT THE CENTER AND ADJACENT THE MARGINAL EDGES THEREOF, SAID SURFACES ESTABLISHING THE SOLE AREAS OF CONTACT BETWEEN SAID ONE AND SAID INTERMEDIATE PLATES AND SAID CENTER SURFACES BEING GENERALLY SPHERICAL; A SPACE BETWEEN SAID ONE AND SAID INTERMEDIATE PLATES RADIALLY INWARD OF AND FROM THE MARGINAL EDGE SURFACES AFORESAID WHEREBY SAID ONE PLATE IS CAPABLE OF NUTATION ABOUT SAID CENTER SURFACES; A RESILIENT MEMBER BETWEEN THE MARGINAL EDGES OF SAID PAIR OF PLATES RADIALLY OUTWARD OF SAID CONCENTRIC SURFACES; AND A CLAMP ENGAGING SAID PAIR OF PLATES ACROSS SAID RESILIENT MEMBER, SAID CLAMP APPLYING A UNIFORM FORCE LESS THAN THAT REQUIRED TO FULLY COMPRESS THE RESILIENT MEMBER. 